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Related Party Transactions (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 26, 2019	Mar. 28, 2020	Mar. 30, 2019	Dec. 28, 2019
Related Party Transaction [Line Items]
Cost method investments		$ 0.4
MWT
Related Party Transaction [Line Items]
Loss on disposal	$ 2.6
Powersem
Related Party Transaction [Line Items]
Ownership percentage		45.00%
Revenue from related parties		$ 0.4	$ 0.1
Purchase from related party		0.2	0.8
Receivable from related parties		0.1		$ 0.0
Payables to related parties		$ 0.1		0.2
EB Tech
Related Party Transaction [Line Items]
Ownership percentage		19.00%
Revenue from related parties		$ 0.0	0.0
Purchase from related party		0.0	0.1
Receivable from related parties		0.0		0.0
Payables to related parties		$ 0.0		0.0
ATEC
Related Party Transaction [Line Items]
Ownership percentage		24.00%
Revenue from related parties		$ 0.0	0.0
Purchase from related party		1.8	$ 1.5
Receivable from related parties		0.0		0.0
Payables to related parties		$ 0.0		$ 0.1